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Wang K.,Harbin Institute of Technology | Jia L.,Heilongjiang Scientific Research Institute of Environmental Protection | Huang L.,Harbin University of Commerce | Cui C.,Harbin Institute of Technology | And 3 more authors.
Harbin Gongye Daxue Xuebao/Journal of Harbin Institute of Technology | Year: 2014

To investigate the pollution characteristics of water soluble ions in PM2.5 and PM10 under severe haze days, both PM2.5 and PM10samples were collected in a city of northeast China under severe haze days during October 20-22, 2013. Nine water-soluble ions in PM2.5 and PM10 including F-, Cl-, NO3 -, SO4 2-, Na+, NH4 +, K+, Mg2+ and Ca2+ were analyzed. The results showed that the concentrations of all water-soluble ions mass concentration in night were higher than those in day time, with a ratio of 1.68 for PM2.5 in haze days. The concentrations of SO4 2-, NO3 - and NH4 + were higher and their percentage in PM2.5 were 11.03%, 8.3% and 7.39% in haze days, the same results in PM10 were obtained. The percentages of K+ and Ca2+ in haze and non-haze periods were similar. Based on the ratio of different ions, the pollution from stationary sources were higher than that from mobile sources in haze days, this showed that meteorological factors had greater influences. In comparison with the data of water soluble ions during October and November of 2009, the concentrations from mobile sources were on the rise. ©, 2014, Harbin Gongye Daxue Xuebao/Journal of Harbin Institute of Technology. All right reserved. Source

Mohammed M.O.A.,Harbin Institute of Technology | Mohammed M.O.A.,University of Khartoum | Song W.-W.,Harbin Institute of Technology | Ma Y.-L.,Tsinghua University | And 9 more authors.
Chemosphere | Year: 2016

In this study we investigated the distribution patterns, infiltration and health risk assessment of PM2.5-bound PAHs in indoor and outdoor air done in Harbin city, northeastern China. Simultaneous indoor and outdoor sampling was done to collect 264 PM2.5 samples from four sites during winter, summer, and spring. Infiltration of PAHs into indoors was estimated using Retene, Benzo [ghi]perylene and Chrysene as reference compounds, where the latter compound was suggested to be a good estimator and subsequently used for further calculation of infiltration factors (IFs). Modeling with positive matrix factorization (PMF5) and estimation of diagnostic isomeric ratios were applied for identifying sources, where coal combustion, crop residues burning and traffic being the major contributors, particularly during winter. Linear discriminant analysis (LDA) has been utilized to show the distribution patterns of individual PAH congeners. LDA showed that, the greatest seasonal variability was attributed to high molecular weight compounds (HMW PAHs). Potential health risk of PAHs exposure was assessed through relative potency factor approach (RPF). The levels of the sum of 16 US EPA priority PAHs during colder months were very high, with average values of 377 ± 228 ng m- 3 and 102 ± 75.8 ng m- 3, for the outdoors and indoors, respectively. The outdoor levels reported to be 19 times higher than the outdoor concentrations during warmer months (summer + spring), while the indoor concentrations were suggested to be 9 times and 10 times higher than that for indoor summer (average 11.73 ± 4 ng m-3) and indoor spring (9.5 ± 3.3 ng m-3). During nighttime, outdoor PAHs revealed wider range of values compared to datytime which was likely due to outdoor temperature, a weather parameter with the strongest negative influence on ∑16PAHs compared to low impact of relative humidity and wind speed. © 2016 Elsevier Ltd. Source

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